Barrier film material and pattern formation method using the same

ABSTRACT

A resist film made of a chemically amplified resist is formed on a substrate. Subsequently, a barrier film for preventing a component of the resist film from eluting into an immersion liquid or preventing the immersion liquid from permeating into the resist film is formed on the resist film. Thereafter, with an immersion liquid provided on the barrier film, pattern exposure is carried out by selectively irradiating the resist film with exposing light through the barrier film. Then, after removing the barrier film, the resist film having been subjected to the pattern exposure is developed, so as to form a resist pattern made of the resist film.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a Continuation of U.S. application Ser. No.11/058,369, filed Feb. 16, 2005, which claims priority under 35 U.S.C.§119 on Patent Application No. 2004-49323 filed in Japan on Feb. 25,2004, and Patent Application No. 2004-361058 filed in Japan on Dec. 14,2004, the entire contents of which are hereby incorporated by reference.

BACKGROUND OF THE INVENTION

The present invention relates to a material for a barrier film formed ona resist film for use in fabrication process or the like forsemiconductor devices and a pattern formation method using the same.

In accordance with the increased degree of integration of semiconductorintegrated circuits and downsizing of semiconductor devices, there areincreasing demands for further rapid development of lithographytechnique. Currently, pattern formation is carried out throughphotolithography using exposing light of a mercury lamp, KrF excimerlaser, ArF excimer laser or the like, and use of F₂ laser lasing at ashorter wavelength is being examined. However, since there remain alarge number of problems in exposure systems and resist materials,photolithography using exposing light of a shorter wavelength has notbeen put to practical use.

In these circumstances, immersion lithography has been recently proposedfor realizing further refinement of patterns by using conventionalexposing light (for example, see M. Switkes and M. Rothschild,“Immersion lithography at 157 nm”, J. Vac. Sci. Technol., Vol. B19, p.2353 (2001)).

In the immersion lithography, a region in an exposure system sandwichedbetween a projection lens and a resist film formed on a wafer is filledwith a liquid having a refractive index n and therefore, the NA(numerical aperture) of the exposure system has a value n·NA. As aresult, the resolution of the resist film can be improved.

Now, a conventional pattern formation method employing the immersionlithography will be described with reference to FIGS. 20A through 20D.

First, a positive chemically amplified resist material having thefollowing composition is prepared:

Base polymer: poly((norbornene-5-methylene-t-butyl- 2 g carboxylate) (50mol %) - (maleic anhydride) (50 mol %)) Acid generator:triphenylsulfonium triflate 0.06 g Quencher: triethanolamine 0.002 gSolvent: propylene glycol monomethyl ether acetate 20 g

Next, as shown in FIG. 20A, the aforementioned chemically amplifiedresist material is applied on a substrate 1 so as to form a resist film2 with a thickness of 0.35 μm.

Then, as shown in FIG. 20B, with an immersion liquid (water) 3 providedon the resist film 2, pattern exposure is carried out by irradiating theresist film 2 with exposing light 4 of ArF excimer laser with NA of 0.68through a mask 5.

After the pattern exposure, as shown in FIG. 20C, the resist film 2 isbaked with a hot plate at a temperature of 105° C. for 60 seconds, andthe resultant resist film is developed with a 2.38 wt %tetramethylammonium hydroxide aqueous solution (alkaline developer). Inthis manner, a resist pattern 2 a made of an unexposed portion of theresist film 2 and having a line width of 0.09 μm is formed as shown inFIG. 20D.

SUMMARY OF THE INVENTION

As shown in FIG. 20D, however, the resist pattern 2 a formed by theconventional pattern formation method is in a defective shape.

The present inventors have variously examined the reason why the resistpattern formed by the conventional immersion lithography is in adefective shape, resulting in finding the following: The resist filmcannot exhibit its expected performance because a low-molecular-weightcompound such as the acid generator or the quencher is eluted from theresist film 2 into the liquid 3 provided on the resist film 2 or becausethe liquid 3 permeates into the resist film 2. For example, in the caseshown in FIG. 20D, the resist pattern 2 a is in a defective shape with aT-top shaped portion probably because the concentration of an acidgenerated from the acid generator is lowered on the interface between anexposed portion and the unexposed portion of the resist film 2. On thecontrary, when the concentration of the quencher used for deactivatingthe acid is lowered, the resultant resist pattern 2 a is in a defectiveshape with round shoulders.

In either case, when the resist pattern 2 a in such a defective shape isused for etching a target film, the resultant pattern of the target filmis also in a defective shape, which disadvantageously lowers theproductivity and the yield in the fabrication process for semiconductordevices.

In consideration of the aforementioned conventional problem, an objectof the invention is forming a fine resist pattern in a good shape bypreventing the influence of an immersion liquid used in the immersionlithography on a resist film.

The present inventors have found, on the basis of the aforementionedresult of the examination, that a component of a resist film can beprevented from eluting into a liquid or a liquid can be prevented frompermeating into a resist film by forming a barrier film on the resistfilm so as not to allow the resist film to be in direct contact with theliquid provided thereon. Furthermore, the barrier film formed on theresist film has such a composition that its solubility is changed inaccordance with the value of hydrogen ion exponent (pH), so that thebarrier film can be insoluble in the liquid but soluble in a developer.

The present invention was devised on the basis of the aforementionedfindings, and according to the invention, a barrier film for preventinga component of a resist film from eluting into a liquid or forpreventing a liquid from permeating into a resist film is formed on theresist film, so that the resist film can keep its expected performance.Specifically, the present invention is practiced as follows:

The barrier film material of this invention is a material for a barrierfilm formed between a resist film made of a chemically amplified resistand a liquid in performing exposure with the liquid provided above theresist film, and the barrier film prevents a component of the resistfilm from eluting into the liquid or prevents the liquid from permeatinginto the resist film.

According to this invention, in immersion lithography in which a resistfilm made of a chemically amplified resist is exposed with a liquidprovided on the resist film, the barrier film made of the barrier filmmaterial and formed between the resist film and the liquid prevents acomponent, such as an acid generator or a quencher, of the resist filmfrom eluting into the liquid or prevents the liquid from permeating intothe resist film. Therefore, the resist film keeps the expectedperformance of the chemically amplified resist through the exposure. Asa result, a resist pattern can be formed in a good shape.

In the barrier film material of the invention, the barrier filmpreferably has solubility different depending upon a value of hydrogenion exponent (pH). Furthermore, the barrier film is preferably solublein a solution with a value of hydrogen ion exponent (pH) larger than 7.In other words, when the barrier film has a composition, for example,that is insoluble in the liquid but soluble in an alkaline developer,the barrier film does not dissolve in the liquid during the exposure butcan be easily removed after the exposure.

The barrier film material of the invention can include an alkali-solublepolymer and a fluorine-based surface active agent. Since afluorine-based surface active agent has a higher hydrophobic propertythan a surface active agent not including fluorine, when the barrierfilm is made of an alkali-soluble polymer including a fluorine-basedsurface active agent, even if a liquid is provided on the barrier film,the barrier film does not dissolve in the liquid. Accordingly, thebarrier film of the invention can prevent contact between the resistfilm and the liquid, and hence, it can prevent a component of the resistfilm from eluting into the liquid or prevent the liquid from permeatinginto the resist film. A sufficient effect can be attained when thecontent of the fluorine-based surface active agent in the alkali-solublepolymer is approximately 1/100 wt % through 1/10 wt %, which does notlimit the invention, and the content may be smaller or larger.

In a known technique, an antireflection film for preventing reflectionof exposing light is formed on a resist film. A surface active agent issometimes included in the antireflection film, but the concentration ofthe surface active agent in the antireflection film is smaller than thecontent of the fluorine-based surface active agent in the alkali-solublepolymer of this invention by one or more figures. This is because thesurface active agent is included in the antireflection film for thepurpose of improving the application property of the antireflectionfilm. In addition, the antireflection film is water-soluble, and hence,when a large amount of surface active agent is included in theantireflection film, the hydrophobic property of the antireflection filmis so high that it may not be dissolved in water. In contrast, thebarrier film of this invention is insoluble in a neutral or acidicsolution.

The alkali-soluble polymer included in the barrier film material of thisinvention can be at least one of polyvinyl hexafluoroisopropyl alcohol,polyvinyl alcohol, polyacrylic acid, polystyrenesulfonic acid,hydroxyethyl cellulose, polyisoplenesulfonic acid, polyvinyl pyrrolidoneand pullulan.

Furthermore, the fluorine-based surface active agent may have a groupwith a double bond. Also, the group with a double bond may be aperfluoroalkenyl group.

The perfluoroalkenyl group may be a1,1-di(perfluoromethyl)-2-perfluoroethylethenyl group or a1,1-di(perfluoroisopropyl)-2-perfluoromethylethenyl group.

Moreover, the fluorine-based surface active agent having the1,1-di(perfluoromethyl)-2-perfluoroethylethenyl group may be1,1-di(perfluoromethyl)-2-perfluoroethylethenyloxybenzyltrimethylammoniumor 1,1-di(perfluoromethyl)-2-perfluoroethylethenylpolyoxyethylene ether.

Alternatively, the fluorine-based surface active agent having the1,1-di(perfluoroisopropyl)-2-perfluoromethylethenyl group may be1,1-di(perfluoroisopropyl)-2-perfluoromethylethenyloxybenzyltrimethylammoniumor 1,1-di(perfluoroisopropyl)-2-perfluoromethylethenylpolyoxyethyleneether.

Furthermore, the present inventors have found that when a polymer havinga sulfonamide structure is used as the barrier film material, aresultant barrier film including the polymer having the sulfonamidestructure can prevent the contact between the liquid and the resistfilm.

The polymer having a sulfonamide structure is soluble in a solution witha value of hydrogen ion exponent (pH) larger than 7 while it isinsoluble in a neutral or acidic solution. Accordingly, it is notdissolved in a neutral or acidic solution generally having a value of pHof 7 or less and is soluble in an alkaline aqueous solution used as adeveloper, and hence, it can be easily removed after the exposure.

The barrier film of this invention preferably includes a polymer havinga sulfonamide structure.

In this case, the polymer may be polyvinylsulfonamide or apolyvinylsulfonamide derivative. The polyvinylsulfonamide derivative maybe polyvinylsulfone alkylamide, polyvinylsulfone alkylamide fluoride orpolyvinylsulfone substituted alkylamide.

Also, a substituent group of the polyvinylsulfone substituted alkylamidemay be a hydroxyl group, an alkoxy group, an oxo group, an amino groupor an alkylamino group.

The first pattern formation method using the barrier film material ofthis invention includes the steps of forming a resist film made of achemically amplified resist on a substrate; forming a barrier film onthe resist film; performing pattern exposure by selectively irradiatingthe resist film with exposing light with a liquid provided on thebarrier film; removing the barrier film; and forming a resist patternmade of the resist film by developing the resist film after removing thebarrier film, and the barrier film prevents a component of the resistfilm from eluting into the liquid or prevents the liquid from permeatinginto the resist film.

In the first pattern formation method, the barrier film formed on theresist film prevents a component of the resist film from eluting intothe liquid or prevents the liquid from permeating into the resist film,and therefore, the resist film keeps the expected performance of thechemically amplified resist during the pattern exposure. As a result,the resist pattern made of the resist film can be formed in a goodshape. In this case, the barrier film can be removed before thedevelopment with an aqueous solution having a pH value for dissolvingthe barrier film, and examples of such a solution are a developer and adiluted developer. The diluted developer is diluted to an extent of aconcentration lower than a general alkaline developer (i.e., 2.38 wt %tetramethylammonium hydroxide), and the concentration is, for example,approximately 0.001 wt % through 2 wt %, whereas the concentration doesnot limit the invention.

The second pattern formation method using the barrier film material ofthis invention includes the steps of forming a resist film made of achemically amplified resist on a substrate; forming a barrier film onthe resist film; performing pattern exposure by selectively irradiatingthe resist film with exposing light with a liquid provided on thebarrier film; and removing the barrier film and forming a resist patternmade of the resist film by developing the resist film after the patternexposure, and the barrier film prevents a component of the resist filmfrom eluting into the liquid or prevents the liquid from permeating intothe resist film.

In the second pattern formation method, the barrier film formed on theresist film prevents a component of the resist film from eluting intothe liquid or prevents the liquid from permeating into the resist filmin the same manner as in the first pattern formation method, andtherefore, the resist film keeps the expected performance of thechemically amplified resist during the pattern exposure. As a result,the resist pattern made of the resist film can be formed in a goodshape.

A difference between the first pattern formation method and the secondpattern formation method is that the barrier film formed on the resistfilm is removed before the development in the first pattern formationmethod while it is removed during the development with a developer inthe second pattern formation method. In the case of the first patternformation method, since the barrier film is removed before thedevelopment, the development processing is generally proceeded.Alternatively, in the case of the second pattern formation method, sincethe barrier film is removed during the development, the dissolutioncharacteristic of the resist can be controlled, resulting in improvingthe dissolution characteristic of the resist. The control of thedissolution characteristic will be described later.

The first or second pattern formation method preferably furtherincludes, before the step of performing pattern exposure, a step ofannealing the barrier film. When the barrier film is thus annealed, thedenseness of the barrier film is improved and hence its insolubleproperty in the liquid is improved. It is noted that the barrier filmshould be annealed at a temperature of an appropriate range because thebarrier film is difficult to remove by dissolving it if its denseness isexcessively improved. The appropriate range of the annealing temperaturedepends upon the composition of the barrier film and is, for example,approximately 100° C. through 150° C., which does not limit theinvention.

In the first or second pattern formation method, the barrier filmpreferably has solubility different depending upon a value of hydrogenion exponent (pH). When the barrier film has such a composition that itis insoluble in the liquid but is soluble in an alkaline developer, thebarrier film can be easily and definitely removed after the patternexposure.

In the first or second pattern formation method, the barrier filmpreferably includes an alkali-soluble polymer and a fluorine-basedsurface active agent. Specifically, the compounds described with respectto the barrier film material of this invention may be used as thealkali-soluble polymer and the fluorine-based surface active agent.

In the first or second pattern formation method, the barrier filmpreferably includes a polymer having a sulfonamide structure.Specifically, the compounds described with respect to the barrier filmmaterial of this invention may be used as the polymer having asulfonamide structure.

In the first or second pattern formation method, the liquid may be wateror perfluoropolyether. Also, the liquid may include an additive such asa surface active agent.

Alternatively, in the first or second pattern formation method, theliquid may be an acidic solution. Examples of the acidic solution are aphosphoric acid aqueous solution and a cesium sulfate aqueous solution,which does not limit the invention.

In the first or second pattern formation method, the exposing light maybe KrF excimer laser, ArF excimer laser, F₂ laser, ArKr laser or Ar₂laser.

BRIEF DESCRIPTION OF THE DRAWINGS

FIGS. 1A, 1B, 1C and 1D are cross-sectional views for showing proceduresin a pattern formation method using a barrier film material according toEmbodiment 1 of the invention;

FIGS. 2A and 2B are cross-sectional views for showing other proceduresin the pattern formation method using the barrier film material ofEmbodiment 1;

FIGS. 3A, 3B, 3C and 3D are cross-sectional views for showing proceduresin a pattern formation method using a barrier film material according toEmbodiment 2 of the invention;

FIGS. 4A, 4B and 4C are cross-sectional views for showing otherprocedures in the pattern formation method using the barrier filmmaterial of Embodiment 2;

FIGS. 5A, 5B, 5C and 5D are cross-sectional views for showing proceduresin a pattern formation method using a barrier film material according toEmbodiment 3 of the invention;

FIG. 6 is a cross-sectional view for showing another procedure in thepattern formation method using the barrier film material of Embodiment3;

FIG. 7 is a graph for explaining control of solubility of a resist inthe pattern formation method using the barrier film material ofEmbodiment 3;

FIGS. 8A, 8B, 8C and 8D are cross-sectional views for showing proceduresin a pattern formation method using a barrier film material according toEmbodiment 4 of the invention;

FIGS. 9A and 9B are cross-sectional views for showing other proceduresin the pattern formation method using the barrier film material ofEmbodiment 4;

FIGS. 10A, 10B, 10C and 10D are cross-sectional views for showingprocedures in a pattern formation method using a barrier film materialaccording to Embodiment 5 of the invention;

FIGS. 11A and 11B are cross-sectional views for showing other proceduresin the pattern formation method using the barrier film material ofEmbodiment 5;

FIGS. 12A, 12B, 12C and 12D are cross-sectional views for showingprocedures in a pattern formation method using a barrier film materialaccording to Embodiment 6 of the invention;

FIGS. 13A and 13B are cross-sectional views for showing other proceduresin the pattern formation method using the barrier film material ofEmbodiment 6;

FIGS. 14A, 14B, 14C and 14D are cross-sectional views for showingprocedures in a pattern formation method using a barrier film materialaccording to Embodiment 7 of the invention;

FIGS. 15A, 15B and 15C are cross-sectional views for showing otherprocedures in the pattern formation method using the barrier filmmaterial of Embodiment 7;

FIGS. 16A, 16B, 16C and 16D are cross-sectional views for showingprocedures in a pattern formation method using a barrier film materialaccording to Embodiment 8 of the invention;

FIG. 17 is a cross-sectional view for showing another procedure in thepattern formation method using the barrier film material of Embodiment8;

FIGS. 18A, 18B, 18C and 18D are cross-sectional views for showingprocedures in a pattern formation method using a barrier film materialaccording to Embodiment 9 of the invention;

FIGS. 19A and 19B are cross-sectional views for showing other proceduresin the pattern formation method using the barrier film material ofEmbodiment 9; and

FIGS. 20A, 20B, 20C and 20D are cross-sectional views for showingprocedures in a conventional pattern formation method employingimmersion lithography.

DETAILED DESCRIPTION OF THE INVENTION Embodiment 1

A pattern formation method using a barrier film material according toEmbodiment 1 of the invention will now be described with reference toFIGS. 1A through 1D, 2A and 2B.

First, a positive chemically amplified resist material having thefollowing composition is prepared:

Base polymer: poly((norbornene-5-methylene-t-butyl- 2 g carboxylate) (50mol %) - (maleic anhydride) (50 mol %)) Acid generator:triphenylsulfonium triflate 0.06 g Quencher: triethanolamine 0.002 gSolvent: propylene glycol monomethyl ether acetate 20 g

Next, as shown in FIG. 1A, the aforementioned chemically amplifiedresist material is applied on a substrate 101 so as to form a resistfilm 102 with a thickness of 0.35 μm.

Then, as shown in FIG. 1B, a barrier film 103 that is made of a barrierfilm material having the following composition, has a thickness of 0.06μm and is different in its solubility depending upon the value of pH isformed on the resist film 102 by, for example, spin coating:

Alkali-soluble polymer: polyvinyl alcohol 1 g Fluorine-based surfaceactive agent: 1,1-di(perfluoro- 0.0003 gmethyl)-2-perfluoroethylethenyloxybenzyltrimethyl- ammonium Solvent:isobutyl alcohol 20 g

Next, as shown in FIG. 1C, with an immersion liquid 104 of waterprovided between the barrier film 103 and a projection lens 106 by, forexample, a puddle method, pattern exposure is carried out by irradiatingthe resist film 102 through the barrier film 103 with exposing light 105of ArF excimer laser with NA of 0.68 having passed through a mask (notshown).

After the pattern exposure, as shown in FIG. 1D, the resist film 102 isbaked with a hot plate at a temperature of 105° C. for 60 seconds (postexposure bake).

Next, as shown in FIG. 2A, the barrier film 103 is removed with, forexample, a 0.01 wt % tetramethylammonium hydroxide aqueous solution(diluted alkaline developer). Thereafter, the resultant resist film 102is developed with a 2.38 wt % tetramethylammonium hydroxide aqueoussolution (alkaline developer). In this manner, a resist pattern 102 amade of an unexposed portion of the resist film 102 and having a linewidth of 0.09 μm is formed in a good shape as shown in FIG. 2B.

In this manner, according to Embodiment 1, before carrying out thepattern exposure shown in FIG. 1C, the barrier film 103 including thealkali-soluble polymer and the fluorine-based surface active agent isformed on the resist film 102. Therefore, the resist film 102 is neverin direct contact with the immersion liquid 104. Accordingly, acomponent of the resist film 102 such as the acid generator or thequencher can be prevented from eluting into the immersion liquid 104 orthe immersion liquid 104 can be prevented from permeating into theresist film 102 on the contrary, and hence, the resist film 102 keepsthe expected performance of the chemically amplified resist through theexposure and the post exposure bake performed thereafter. As a result,the resist pattern 102 a made of the resist film 102 is not degraded inits shape.

Embodiment 2

A pattern formation method using a barrier film material according toEmbodiment 2 of the invention will now be described with reference toFIGS. 3A through 3D and 4A through 4C.

First, a positive chemically amplified resist material having thefollowing composition is prepared:

Base polymer: poly((norbornene-5-methylene-t-butyl- 2 g carboxylate) (50mol %) - (maleic anhydride) (50 mol %)) Acid generator:triphenylsulfonium triflate 0.06 g Quencher: triethanolamine 0.002 gSolvent: propylene glycol monomethyl ether acetate 20 g

Next, as shown in FIG. 3A, the aforementioned chemically amplifiedresist material is applied on a substrate 201 so as to form a resistfilm 202 with a thickness of 0.35 μm.

Then, as shown in FIG. 3B, a barrier film 203 that is made of a barrierfilm material having the following composition, has a thickness of 0.07μm and is different in its solubility depending upon the value of pH isformed on the resist film 202 by, for example, the spin coating:

Alkali-soluble polymer: polyvinyl pyrrolidone 1 g Fluorine-based surfaceactive agent: 1,1-di(perfluoro- 0.0005 gisopropyl)-2-perfluoromethylethenyloxybenzyltrimethyl- ammonium Solvent:n-butyl alcohol 20 g

Next, as shown in FIG. 3C, the barrier film 203 is annealed with a hotplate at a temperature of 120° C. for 90 seconds, so as to improve thedenseness of the barrier film 203.

After the annealing, as shown in FIG. 3D, with an immersion liquid 204of water provided between the barrier film 203 and a projection lens 206by, for example, the puddle method, pattern exposure is carried out byirradiating the resist film 202 through the barrier film 203 withexposing light 205 of ArF excimer laser with NA of 0.68 having passedthrough a mask (not shown).

After the pattern exposure, as shown in FIG. 4A, the resist film 202 isbaked with a hot plate at a temperature of 105° C. for 60 seconds (postexposure bake).

Next, as shown in FIG. 4B, the barrier film 203 is removed with, forexample, a 0.005 wt % tetramethylammonium hydroxide aqueous solution(diluted alkaline developer). Thereafter, the resultant resist film 202is developed with a 2.38 wt % tetramethylammonium hydroxide aqueoussolution (alkaline developer). In this manner, a resist pattern 202 amade of an unexposed portion of the resist film 202 and having a linewidth of 0.09 μm is formed in a good shape as shown in FIG. 4C.

In this manner, according to Embodiment 2, before carrying out thepattern exposure shown in FIG. 3D, the barrier film 203 including thealkali-soluble polymer and the fluorine-based surface active agent isformed on the resist film 202. Therefore, the resist film 202 is neverin direct contact with the immersion liquid 204. Accordingly, acomponent of the resist film 202 such as the acid generator or thequencher can be prevented from eluting into the immersion liquid 204 orthe immersion liquid 204 can be prevented from permeating into theresist film 202 on the contrary, and hence, the resist film 202 keepsthe expected performance of the chemically amplified resist through theexposure and the post exposure bake performed thereafter. As a result,the resist pattern 202 a made of the resist film 202 is not degraded inits shape.

In addition, in Embodiment 2, since the barrier film 203 is annealed forimproving the denseness as shown in FIG. 3C before the pattern exposure,the insolubility of the barrier film 203 in the immersion liquid 204(water) is increased. Therefore, the function of the barrier film 203 asa barrier for preventing the acid generator or the like from elutingfrom the resist film 202 into the immersion liquid 204 can be improved.

Embodiment 3

A pattern formation method using a barrier film material according toEmbodiment 3 of the invention will now be described with reference toFIGS. 5A through 5D and 6.

First, a positive chemically amplified resist material having thefollowing composition is prepared:

Base polymer: poly((norbornene-5-methylene-t-butyl- 2 g carboxylate) (50mol %) - (maleic anhydride) (50 mol %)) Acid generator:triphenylsulfonium triflate 0.06 g Quencher: triethanolamine 0.002 gSolvent: propylene glycol monomethyl ether acetate 20 g

Next, as shown in FIG. 5A, the aforementioned chemically amplifiedresist material is applied on a substrate 301 so as to form a resistfilm 302 with a thickness of 0.35 μm.

Then, as shown in FIG. 5B, a barrier film 303 that is made of a barrierfilm material having the following composition, has a thickness of 0.05μm and is different in its solubility depending upon the value of pH isformed on the resist film 302 by, for example, the spin coating:

Alkali-soluble polymer: polyacrylic acid 1 g Fluorine-based surfaceactive agent: 1,1-di(perfluoro- 0.0006 gmethyl)-2-perfluoroethylethenylpolyoxyethylene ether Solvent: n-butylalcohol 20 g

Next, as shown in FIG. 5C, with an immersion liquid 304 of waterprovided between the barrier film 303 and a projection lens 306 by, forexample, the puddle method, pattern exposure is carried out byirradiating the resist film 302 through the barrier film 303 withexposing light 305 of ArF excimer laser with NA of 0.68 having passedthrough a mask (not shown).

After the pattern exposure, as shown in FIG. 5D, the resist film 302 isbaked with a hot plate at a temperature of 105° C. for 60 seconds (postexposure bake).

Next, the barrier film 303 is removed and the resultant resist film 302is developed with a 2.38 wt % tetramethylammonium hydroxide aqueoussolution (alkaline developer). In this manner, a resist pattern 302 amade of an unexposed portion of the resist film 302 and having a linewidth of 0.09 μm is formed in a good shape as shown in FIG. 6.

In this manner, according to Embodiment 3, before carrying out thepattern exposure shown in FIG. 5C, the barrier film 303 including thealkali-soluble polymer and the fluorine-based surface active agent isformed on the resist film 302. Therefore, the resist film 302 is neverin direct contact with the immersion liquid 304. Accordingly, acomponent of the resist film 302 such as the acid generator or thequencher can be prevented from eluting into the immersion liquid 304 orthe immersion liquid 304 can be prevented from permeating into theresist film 302 on the contrary, and hence, the resist film 302 keepsthe expected performance of the chemically amplified resist through theexposure and the post exposure bake performed thereafter. As a result,the resist pattern 302 a made of the resist film 302 is not degraded inits shape.

In the pattern formation method of Embodiment 3, the barrier film 303 isremoved during the development, namely, with the alkaline developer,differently from those of Embodiments 1 and 2. Thus, the dissolutioncharacteristic of the resist film 302 can be controlled. The control ofthe dissolution characteristic will now be described with reference toFIG. 7.

In general, when the dissolution characteristic of a resist in adeveloper is high, the dissolution rate is abruptly increased whenexposure exceeds a given threshold value as shown with a graph A of abroken line in FIG. 7. As the change of the dissolution rate against theexposure is more abrupt, a difference in the solubility between anexposed portion and an unexposed portion of the resist film 302 islarger, and hence, higher resolution can be attained, namely, the resistpattern 302 a can be formed in a better shape. Accordingly, in the casewhere the barrier film 303 is removed simultaneously with thedevelopment, the dissolution rate is wholly lowered during the removalof the barrier film 303 as shown with a graph B of a solid line in FIG.7, and hence, the change in a portion surrounded with a circle C in thegraph B can be reduced to be approximated to a flat portion of the graphA. As a result, in the case where the actual resist has the dissolutioncharacteristic as shown with the graph B, the dissolution rate attainedwith smaller exposure can be adjusted to attain a comparatively constantstate with small exposure and a low dissolution rate within a givenrange. Accordingly, the difference in the solubility between an exposedportion and an unexposed portion of the resist film 302 can besubstantially increased, resulting in easily forming a resist pattern ina good shape.

Embodiment 4

A pattern formation method using a barrier film material according toEmbodiment 4 of the invention will now be described with reference toFIGS. 8A through 8D, 9A and 9B.

First, a positive chemically amplified resist material having thefollowing composition is prepared:

Base polymer: poly((norbornene-5-methylene-t-butyl- 2 g carboxylate) (50mol %) - (maleic anhydride) (50 mol %)) Acid generator:triphenylsulfonium triflate 0.06 g Quencher: triethanolamine 0.002 gSolvent: propylene glycol monomethyl ether acetate 20 g

Next, as shown in FIG. 8A, the aforementioned chemically amplifiedresist material is applied on a substrate 401 so as to form a resistfilm 402 with a thickness of 0.35 μm.

Then, as shown in FIG. 8B, a barrier film 403 that is made of a barrierfilm material having the following composition, has a thickness of 0.04μm and is different in its solubility depending upon the value of pH isformed on the resist film 402 by, for example, the spin coating:

Alkali-soluble polymer: polyvinyl hexafluoroisopropyl 1 g alcoholFluorine-based surface active agent: 1,1-di(perfluoro- 0.0005 gisopropyl)-2-perfluoromethylethenylpolyoxyethylene ether Solvent:isobutyl alcohol 20 g

Next, as shown in FIG. 8C, the barrier film 403 is annealed with a hotplate at a temperature of 115° C. for 90 seconds, so as to improve thedenseness of the barrier film 403.

After the annealing, as shown in FIG. 8D, with an immersion liquid 404of water provided between the barrier film 403 and a projection lens 406by, for example, the puddle method, pattern exposure is carried out byirradiating the resist film 402 through the barrier film 403 withexposing light 405 of ArF excimer laser with NA of 0.68 having passedthrough a mask (not shown).

After the pattern exposure, as shown in FIG. 9A, the resist film 402 isbaked with a hot plate at a temperature of 105° C. for 60 seconds (postexposure bake).

Next, the barrier film 403 is removed and the resultant resist film 402is developed with a 2.38 wt % tetramethylammonium hydroxide aqueoussolution (alkaline developer). In this manner, a resist pattern 402 amade of an unexposed portion of the resist film 402 and having a linewidth of 0.09 μm is formed in a good shape as shown in FIG. 9B.

In this manner, according to Embodiment 4, before carrying out thepattern exposure shown in FIG. 8D, the barrier film 403 including thealkali-soluble polymer and the fluorine-based surface active agent isformed on the resist film 402. Therefore, the resist film 402 is neverin direct contact with the immersion liquid 404. Accordingly, acomponent of the resist film 402 such as the acid generator or thequencher can be prevented from eluting into the immersion liquid 404 orthe immersion liquid 404 can be prevented from permeating into theresist film 402 on the contrary, and hence, the resist film 402 keepsthe expected performance of the chemically amplified resist through theexposure and the post exposure bake performed thereafter. As a result,the resist pattern 402 a made of the resist film 402 is not degraded inits shape.

In addition, in Embodiment 4, since the barrier film 403 is annealed forimproving the denseness as shown in FIG. 8C before the pattern exposure,the insolubility of the barrier film 403 in the immersion liquid 404(water) is increased. Therefore, the function of the barrier film 403 asa barrier for preventing the acid generator or the like from elutingfrom the resist film 402 into the immersion liquid 404 can be improved.

Also, since the barrier film 403 is removed during the development,namely, with the alkaline developer, in the same manner as in Embodiment3, the dissolution characteristic of the resist film 402 can becontrolled.

Embodiment 5

A pattern formation method using a barrier film material according toEmbodiment 5 of the invention will now be described with reference toFIGS. 10A through 10D, 11A and 11B.

First, a positive chemically amplified resist material having thefollowing composition is prepared:

Base polymer: poly((styrenehexafluoroisopropyl alcohol) 2 g (40 mol %) -(α-trifluoromethyl-t-butylacrylate) (60 mol %)) Acid generator:triphenylsulfonium triflate 0.06 g Quencher: triethanolamine 0.003 gSolvent: propylene glycol monomethyl ether acetate 20 g

Next, as shown in FIG. 1A, the aforementioned chemically amplifiedresist material is applied on a substrate 501 so as to form a resistfilm 502 with a thickness of 0.15 μm.

Then, as shown in FIG. 10B, a barrier film 503 that is made of a barrierfilm material having the following composition, has a thickness of 0.03μm and is different in its solubility depending upon the value of pH isformed on the resist film 502 by, for example, the spin coating:

Alkali-soluble polymer: polyvinyl alcohol 1 g Fluorine-based surfaceactive agent: 1,1-di(perfluoro- 0.0003 gmethyl)-2-perfluoroethylethenyloxybenzyltrimethyl- ammonium Solvent:isoamyl alcohol 20 g

Next, as shown in FIG. 10C, with an immersion liquid 504 ofperfluoropolyether provided between the barrier film 503 and aprojection lens 506 by, for example, the puddle method, pattern exposureis carried out by irradiating the resist film 502 through the barrierfilm 503 with exposing light 505 of F₂ laser with NA of 0.85 havingpassed through a mask (not shown).

After the pattern exposure, as shown in FIG. 10D, the resist film 502 isbaked with a hot plate at a temperature of 110° C. for 60 seconds (postexposure bake).

Next, as shown in FIG. 11A, the barrier film 503 is removed with, forexample, a 0.01 wt % tetramethylammonium hydroxide aqueous solution(diluted alkaline developer) and thereafter, the resultant resist film502 is developed with a 2.38 wt % tetramethylammonium hydroxide aqueoussolution (alkaline developer). In this manner, a resist pattern 502 amade of an unexposed portion of the resist film 502 and having a linewidth of 0.07 μm is formed in a good shape as shown in FIG. 11B.

In this manner, according to Embodiment 5, before carrying out thepattern exposure shown in FIG. 10C, the barrier film 503 including thealkali-soluble polymer and the fluorine-based surface active agent isformed on the resist film 502. Therefore, the resist film 502 is neverin direct contact with the immersion liquid 504. Accordingly, acomponent of the resist film 502 such as the acid generator or thequencher can be prevented from eluting into the immersion liquid 504 orthe immersion liquid 504 can be prevented from permeating into theresist film 502 on the contrary, and hence, the resist film 502 keepsthe expected performance of the chemically amplified resist through theexposure and the post exposure bake performed thereafter. As a result,the resist pattern 502 a made of the resist film 502 is not degraded inits shape.

Also in Embodiment 5, the annealing for improving the denseness may beperformed on the barrier film 503 before the pattern exposure.

Also, in the same manner as in Embodiments 3 and 4, the barrier film 503may be removed not before the development but during the development.

In each of Embodiments 1 through 5, the alkali-soluble polymer includedin the barrier film is polyvinyl hexafluoroisopropyl alcohol, polyvinylalcohol, polyvinyl pyrrolidone, polyacrylic acid or polystyrenesulfonicacid, and apart from these polymers, hydroxyethyl cellulose,polyisoprenesulfonic acid or pullulan may be used.

Furthermore, the fluorine-based surface active agent included in thebarrier film is not limited to those used in Embodiments 1 through 5 butmay be a surface active agent having a group with a double bond, such asa surface active agent having a perfluoroalkenyl group.

Embodiment 6

A pattern formation method using a barrier film material according toEmbodiment 6 of the invention will now be described with reference toFIGS. 12A through 12D, 13A and 13B.

First, a positive chemically amplified resist material having thefollowing composition is prepared:

Base polymer: poly((norbornene-5-methylene-t-butyl- 2 g carboxylate) (50mol %) - (maleic anhydride) (50 mol %)) Acid generator:triphenylsulfonium triflate 0.06 g Quencher: triethanolamine 0.002 gSolvent: propylene glycol monomethyl ether acetate 20 g

Next, as shown in FIG. 12A, the aforementioned chemically amplifiedresist material is applied on a substrate 601 so as to form a resistfilm 602 with a thickness of 0.35 μm.

Then, as shown in FIG. 12B, a barrier film 603 that is made of a barrierfilm material having the following composition, has a thickness of 0.07μm and is different in its solubility depending upon the value of pH isformed on the resist film 602 by, for example, the spin coating:

Polymer: polyvinyl sulfonamide  1 g Solvent: isopropyl alcohol 20 g

Next, as shown in FIG. 12C, with an immersion liquid 604 of waterprovided between the barrier film 603 and a projection lens 606 by, forexample, the puddle method, pattern exposure is carried out byirradiating the resist film 602 through the barrier film 603 withexposing light 605 of ArF excimer laser with NA of 0.68 having passedthrough a mask (not shown).

After the pattern exposure, as shown in FIG. 12D, the resist film 602 isbaked with a hot plate at a temperature of 105° C. for 60 seconds (postexposure bake).

Next, as shown in FIG. 13A, the barrier film 603 is removed with, forexample, a 0.01 wt % tetramethylammonium hydroxide aqueous solution(diluted alkaline developer). Thereafter, the resultant resist film 602is developed with a 2.38 wt % tetramethylammonium hydroxide aqueoussolution (alkaline developer). In this manner, a resist pattern 602 amade of an unexposed portion of the resist film 602 and having a linewidth of 0.09 μm is formed in a good shape as shown in FIG. 13B.

In this manner, according to Embodiment 6, before carrying out thepattern exposure shown in FIG. 12C, the barrier film 603 including thepolymer having a sulfonamide structure (i.e., polyvinyl sulfonamide) isformed on the resist film 602. Therefore, the resist film 602 is neverin direct contact with the immersion liquid 604. Accordingly, acomponent of the resist film 602 such as the acid generator or thequencher can be prevented from eluting into the immersion liquid 604 orthe immersion liquid 604 can be prevented from permeating into theresist film 602 on the contrary, and hence, the resist film 602 keepsthe expected performance of the chemically amplified resist through theexposure and the post exposure bake performed thereafter. As a result,the resist pattern 602 a made of the resist film 602 is not degraded inits shape.

Embodiment 7

A pattern formation method using a barrier film material according toEmbodiment 7 of the invention will now be described with reference toFIGS. 14A through 14D and 15A through 15C.

First, a positive chemically amplified resist material having thefollowing composition is prepared:

Base polymer: poly((norbornene-5-methylene-t-butyl- 2 g carboxylate) (50mol %) - (maleic anhydride) (50 mol %)) Acid generator:triphenylsulfonium triflate 0.06 g Quencher: triethanolamine 0.002 gSolvent: propylene glycol monomethyl ether acetate 20 g

Next, as shown in FIG. 14A, the aforementioned chemically amplifiedresist material is applied on a substrate 701 so as to form a resistfilm 702 with a thickness of 0.35 μm.

Then, as shown in FIG. 14B, a barrier film 703 that is made of a barrierfilm material having the following composition, has a thickness of 0.06μm and is different in its solubility depending upon the value of pH isformed on the resist film 702 by, for example, the spin coating:

Polymer: polyvinyl sulfone-N-ethylamide  1 g Solvent: n-butyl alcohol 20g

Next, as shown in FIG. 14C, the barrier film 703 is annealed with a hotplate at a temperature of 120° C. for 90 seconds, so as to improve thedenseness of the barrier film 703.

After the annealing, as shown in FIG. 14D, with an immersion liquid 704of water provided between the barrier film 703 and a projection lens 706by, for example, the puddle method, pattern exposure is carried out byirradiating the resist film 702 through the barrier film 703 withexposing light 705 of ArF excimer laser with NA of 0.68 having passedthrough a mask (not shown).

After the pattern exposure, as shown in FIG. 15A, the resist film 702 isbaked with a hot plate at a temperature of 105° C. for 60 seconds (postexposure bake).

Next, as shown in FIG. 15B, the barrier film 703 is removed with, forexample, a 0.005 wt % tetramethylammonium hydroxide aqueous solution(diluted alkaline developer). Thereafter, the resultant resist film 702is developed with a 2.38 wt % tetramethylammonium hydroxide aqueoussolution (alkaline developer). In this manner, a resist pattern 702 amade of an unexposed portion of the resist film 702 and having a linewidth of 0.09 μm is formed in a good shape as shown in FIG. 15C.

In this manner, according to Embodiment 7, before carrying out thepattern exposure shown in FIG. 14D, the barrier film 703 including thepolymer having a sulfonamide structure (i.e., polyvinylsulfone-N-ethylamide) is formed on the resist film 702. Therefore, theresist film 702 is never in direct contact with the immersion liquid704. Accordingly, a component of the resist film 702 such as the acidgenerator or the quencher can be prevented from eluting into theimmersion liquid 704 or the immersion liquid 704 can be prevented frompermeating into the resist film 702 on the contrary, and hence, theresist film 702 keeps the expected performance of the chemicallyamplified resist through the exposure and the post exposure bakeperformed thereafter. As a result, the resist pattern 702 a made of theresist film 702 is not degraded in its shape.

In addition, in Embodiment 7, since the barrier film 703 is annealed forimproving the denseness as shown in FIG. 14C before the patternexposure, the insolubility of the barrier film 703 in the immersionliquid 704 (water) is increased. Therefore, the function of the barrierfilm 703 as a barrier for preventing the acid generator or the like fromeluting from the resist film 702 into the immersion liquid 704 can beimproved.

Embodiment 8

A pattern formation method using a barrier film material according toEmbodiment 8 of the invention will now be described with reference toFIGS. 16A through 16D and 17.

First, a positive chemically amplified resist material having thefollowing composition is prepared:

Base polymer: poly((norbornene-5-methylene-t-butyl- 2 g carboxylate) (50mol %) - (maleic anhydride) (50 mol %)) Acid generator:triphenylsulfonium triflate 0.06 g Quencher: triethanolamine 0.002 gSolvent: propylene glycol monomethyl ether acetate 20 g

Next, as shown in FIG. 16A, the aforementioned chemically amplifiedresist material is applied on a substrate 801 so as to form a resistfilm 802 with a thickness of 0.35 μm.

Then, as shown in FIG. 16B, a barrier film 803 that is made of a barrierfilm material having the following composition, has a thickness of 0.07μm and is different in its solubility depending upon the value of pH isformed on the resist film 802 by, for example, the spin coating:

Polymer: polyvinyl sulfone-N-chloromethylamide  1 g Solvent: isopropylalcohol 20 g

Next, as shown in FIG. 16C, with an immersion liquid 804 of waterprovided between the barrier film 803 and a projection lens 806 by, forexample, the puddle method, pattern exposure is carried out byirradiating the resist film 802 through the barrier film 803 withexposing light 805 of ArF excimer laser with NA of 0.68 having passedthrough a mask (not shown).

After the pattern exposure, as shown in FIG. 16D, the resist film 802 isbaked with a hot plate at a temperature of 105° C. for 60 seconds (postexposure bake).

Next, the barrier film 803 is removed and the resultant resist film 802is developed with a 2.38 wt % tetramethylammonium hydroxide aqueoussolution (alkaline developer). In this manner, a resist pattern 802 amade of an unexposed portion of the resist film 802 and having a linewidth of 0.09 μm is formed in a good shape as shown in FIG. 17.

In this manner, according to Embodiment 8, before carrying out thepattern exposure shown in FIG. 16C, the barrier film 803 including thepolymer having a sulfonamide structure (i.e., polyvinylsulfone-N-chloromethylamide) is formed on the resist film 802.Therefore, the resist film 802 is never in direct contact with theimmersion liquid 804. Accordingly, a component of the resist film 802such as the acid generator or the quencher can be prevented from elutinginto the immersion liquid 804 or the immersion liquid 804 can beprevented from permeating into the resist film 802 on the contrary, andhence, the resist film 802 keeps the expected performance of thechemically amplified resist through the exposure and the post exposurebake performed thereafter. As a result, the resist pattern 802 a made ofthe resist film 802 is not degraded in its shape.

Furthermore, in the same manner as in Embodiment 3, since the barrierfilm 803 is removed during the development, namely, with the alkalinedeveloper, the dissolution characteristic of the resist film 802 can becontrolled.

Embodiment 9

A pattern formation method using a barrier film material according toEmbodiment 9 of the invention will now be described with reference toFIGS. 18A through 18D, 19A and 19B.

First, a positive chemically amplified resist material having thefollowing composition is prepared:

Base polymer: poly((norbornene-5-methylene-t-butyl- 2 g carboxylate) (50mol %) - (maleic anhydride) (50 mol %)) Acid generator:triphenylsulfonium triflate 0.06 g Quencher: triethanolamine 0.002 gSolvent: propylene glycol monomethyl ether acetate 20 g

Next, as shown in FIG. 18A, the aforementioned chemically amplifiedresist material is applied on a substrate 901 so as to form a resistfilm 902 with a thickness of 0.35 μm.

Then, as shown in FIG. 18B, a barrier film 903 that is made of a barrierfilm material having the following composition, has a thickness of 0.08μm and is different in its solubility depending upon the value of pH isformed on the resist film 902 by, for example, the spin coating:

Polymer: polyvinyl sulfone-N-hydroxyethylamide  1 g Solvent: n-amylalcohol 20 g

Next, as shown in FIG. 18C, the barrier film 903 is annealed with a hotplate at a temperature of 115° C. for 90 seconds, so as to improve thedenseness of the barrier film 903.

After the annealing, as shown in FIG. 18D, with an immersion liquid 904of water provided between the barrier film 903 and a projection lens 906by, for example, the puddle method, pattern exposure is carried out byirradiating the resist film 902 through the barrier film 903 withexposing light 905 of ArF excimer laser with NA of 0.68 having passedthrough a mask (not shown).

After the pattern exposure, as shown in FIG. 19A, the resist film 902 isbaked with a hot plate at a temperature of 105° C. for 60 seconds (postexposure bake).

Next, the barrier film 903 is removed and the resultant resist film 902is developed with a 2.38 wt % tetramethylammonium hydroxide aqueoussolution (alkaline developer). In this manner, a resist pattern 902 amade of an unexposed portion of the resist film 902 and having a linewidth of 0.09 μm is formed in a good shape as shown in FIG. 19B.

In this manner, according to Embodiment 9, before carrying out thepattern exposure shown in FIG. 18D, the barrier film 903 including thepolymer having a sulfonamide structure (i.e., polyvinylsulfone-N-hydroxyethylamide) is formed on the resist film 902.Therefore, the resist film 902 is never in direct contact with theimmersion liquid 904. Accordingly, a component of the resist film 902such as the acid generator or the quencher can be prevented from elutinginto the immersion liquid 904 or the immersion liquid 904 can beprevented from permeating into the resist film 902 on the contrary, andhence, the resist film 902 keeps the expected performance of thechemically amplified resist through the exposure and the post exposurebake performed thereafter. As a result, the resist pattern 902 a made ofthe resist film 902 is not degraded in its shape.

In addition, in Embodiment 9, since the barrier film 903 is annealed forimproving the denseness as shown in FIG. 18C before the patternexposure, the insolubility of the barrier film 903 in the immersionliquid 904 (water) is increased. Therefore, the function of the barrierfilm 903 as a barrier for preventing the acid generator or the like fromeluting from the resist film 902 into the immersion liquid 904 can beimproved.

Furthermore, since the barrier film 903 is removed during thedevelopment, namely, with the alkaline developer, in the same manner asin Embodiment 3, the dissolution characteristic of the resist film 902can be controlled.

Although the exposing light is ArF excimer laser in Embodiments 1through 4 and 6 through 9 and is F₂ laser in Embodiment 5, the exposinglight is not limited to them but may be KrF excimer laser, ArKr laser orAr₂ laser instead.

Furthermore, in each of Embodiments 1 through 9, the refractive index ofthe immersion liquid may be increased by adding, for example, cesiumsulfate (Cs₂SO₄) or phosphoric acid (H₃PO₄) to the immersion liquid. Inthis case, the concentration of the cesium sulfate or the phosphoricacid is approximately 1 wt % through 10 wt %, which does not limit theinvention.

Also, the thickness of the barrier film is not limited to the thicknessemployed in each embodiment, which is specifically 0.03 μm through 0.08μm. The lower limit of the thickness is a thickness sufficiently largerfor preventing a component of the resist film from eluting into theimmersion liquid or preventing the immersion liquid from permeating intothe resist film, and the upper limit of the thickness is a thicknesssufficiently smaller for not preventing transmittance of the exposinglight but to be easily removed. For example, the thickness is preferably0.01 μm through 0.15 μm and more preferably approximately 0.02 μmthrough 0.10 μm, which does not limit the invention.

Furthermore, the puddle method is employed for providing the immersionliquid onto the barrier film in each embodiment, which does not limitthe invention, and for example, a dip method in which the wholesubstrate is dipped in the immersion liquid may be employed instead.

Moreover, although a positive chemically amplified resist is used forforming the resist film in each embodiment, the present invention isapplicable also to a negative chemically amplified resist.

As described so far, according to the barrier film material and thepattern formation method using the same of this invention, the influenceof an immersion liquid on a resist film can be prevented, so that aresist pattern can be formed in a good shape. Accordingly, the presentinvention is useful as a method for forming a fine pattern to beemployed in fabrication process or the like for semiconductor devices.

1-52. (canceled)
 53. A pattern formation method comprising: forming aresist film made of a chemically amplified resist material on asubstrate; forming a barrier film on the resist film; performing patternexposure by selectively irradiating the resist film with exposing lightwith water provided on the barrier film; and forming a resist pattern bydeveloping the resist film after the pattern exposure, wherein thebarrier film is made of a barrier film material including analkali-soluble polymer and an alcohol solvent.
 54. The pattern formationmethod of claim 53, wherein the barrier film is removed by an alkalinedeveloper.
 55. The pattern formation method of claim 53, wherein thebarrier film is removed in the forming the resist pattern.
 56. Thepattern formation method of claim 53, wherein the barrier film isremoved by a developer for forming the resist pattern.
 57. The patternformation method of claim 53, wherein the water is provided on thebarrier film by a puddle method.
 58. The pattern formation method ofclaim 53, further comprising annealing the barrier film before theperforming pattern exposure.
 59. The pattern formation method of claim53, wherein the alkali-soluble polymer is at least one of polyvinylhexafluoroisopropyl alcohol, polyvinyl alcohol, polyacrylic acid,polystyrenesulfonic acid, hydroxyethyl cellulose, polyisoprenesulfonicacid, polyvinyl pyrrolidone and pullulan.
 60. The barrier film materialof claim 53, wherein the barrier film material includes a fluorine-basedsurface active agent.
 61. The barrier film material of claim 53, whereinthe exposing light is KrF excimer laser, ArF excimer laser, F₂ laser,ArKr laser or Ar₂ laser.
 62. A method of fabricating a semiconductordevice, the method comprising: forming a target film on a substrate;forming a resist film made of a chemically amplified resist material onthe target film; forming a barrier film on the resist film; performingpattern exposure by selectively irradiating the resist film withexposing light with water provided on the barrier film; forming a resistpattern by developing the resist film after the pattern exposure; andetching the target film by using the resist pattern as an etching mask,wherein the barrier film is made of a barrier film material including analkali-soluble polymer and an alcohol solvent.
 63. The method of claim62, wherein the barrier film is removed by an alkaline developer. 64.The method of claim 62, wherein the barrier film is removed in theforming the resist pattern.
 65. The method of claim 62, wherein thebarrier film is removed by a developer for forming the resist pattern.66. The method of claim 62, wherein the water is provided on the barrierfilm by a puddle method.
 67. The method of claim 62, further comprisingannealing the barrier film before the performing pattern exposure. 68.The method of claim 62, wherein the alkali-soluble polymer is at leastone of polyvinyl hexafluoroisopropyl alcohol, polyvinyl alcohol,polyacrylic acid, polystyrenesulfonic acid, hydroxyethyl cellulose,polyisoprenesulfonic acid, polyvinyl pyrrolidone and pullulan.
 69. Themethod of claim 62, wherein the barrier film material includes afluorine-based surface active agent.
 70. The method of claim 62, whereinthe exposing light is KrF excimer laser, ArF excimer laser, F₂ laser,ArKr laser or Ar₂ laser.